(1) Field of the Invention
The invention relates to digital capture of x-ray images. More specifically, the invention relates to capturing of x-ray images from both transmissive film and reflective filmless plates.
(2) Background
Various scanners for digitizing images from x-ray film are commercially available. For example, Radiographic Digital Imaging of Compton, Calif. produces a lightbox scanner sold under the trademark COBRASCAN.RTM. which uses a charge coupled device (CCD) to capture the image contained on a standard x-ray film when the x-ray film is transported past a reading window.
While traditional x-ray film has been ubiquitous for decades, more recently, filmless x-rays have been taken using a phosphorescent plate. The phosphorescent plate is reflective and erasable, allowing for repeated reuse. An x-ray impregnates the plate with energy which, when subsequently exposed to a particular excitation, is released, recreating the image. Various companies produce readers for these filmless plates, including Fuji Film Ltd. and Eastman Kodak. Such readers typically employ a flying spot laser and photo multiplier tube. The photo multiplier tube captures the image corresponding to the energy being released by excitation of the flying spot laser. The plate is typically transported by a set of rollers which necessitate that the phosphorescent plate be flexible and, in any case, over time, causes a deleterious effect on the plate, resulting in limited reusability. Additionally, these readers are incapable of digitizing conventional x-ray film. Thus, a radiology department is required to have two separate devices for the digitization of images from the different media types.